Magnus
Duke of Östergötland
Prince Magnus of Sweden
Born	25 July 1542
Died	26 June 1595(1595-06-26) (aged 52) Kungsbro [sv]
Burial	Vadstena Abbey
Issue	Lucretia Magnusdotter Gyllenhielm Helena Magnusdotter Gyllenhielm Virginia Magnusdotter Gyllenhielm
House	Vasa
Father	Gustav Vasa of Sweden
Mother	Margareta Leijonhufvud

Swedish Royalty
House of Vasa
Gustav I
Parents Erik Johansson Cecilia Månsdotter Children Eric XIV John III Catherine Cecilia Magnus Anna Sophia Elizabeth Charles IX
Eric XIV
Children Sigrid Gustav
John III
Children Sigismund Anna John
Sigismund
Children Władysław IV John II Casimir John Albert Charles Ferdinand Alexander Charles Anna Catherine Constance
Charles IX
Children Catherine Gustavus Adolphus Maria Elizabeth Christina Charles Philip Grandson Charles X Gustav
Gustavus Adolphus
Children Christina
Christina
v t e

Magnus Vasa (25 July 1542 – 26 June 1595), prince of Sweden, Duke of Östergötland from 1555. Magnus was the third son of King Gustav Vasa. His mother was queen Margareta Leijonhufvud.

Magnus was the only of Gustav Vasa's sons – except for Karl and Sten, who died in infancy – that didn't become king of Sweden. In 1555, he was made Duke of Ostrogothia, Kinda and Ydre, Dalsland, Sundbo härad in Närke, Kåkind, Valla, and the major part of Vadsbo härad in Västergötland. As Duke of Ostrogothia, he lived permanently at Vadstena Castle in Vadstena.

Magnus suffered from a severe mental illness.^[1]: 322 The illness showed its first signs in 1563, and eventually became permanent. In 1574, the responsibility of his fiefs were taken over by his brother King John III, who managed them as his guardian because of his mental condition. A smaller part of them was granted to his other brother, Charles.

Magnus died at the Manorhouse of Kungsbro, outside Linköping, in 1595 and is buried in the Bridgettine Abbey Church in Vadstena.

Many ballads and stories were inspired by Magnus and his alleged interest in mythological creatures such as fairies.

There are many stories about the "Mad Duke", for instance about how he saw a mermaid in the castle moat and threw himself out of a window, nearly drowning himself. There is no proof that this event ever took place, but the story might have evolved from an incident in 1563 when he fell in the moat, during the construction of the castle drawbridge. Geijer and Afzelius note that the alleged mermaid incident appears to have found its way into the ballad "Hertig Magnus och Hafsfrun" ("Herr Mannelig").^[2]

Magnus was never married. He had three confirmed and acknowledged children outside of marriage.

With Valborg Eriksdotter:

1. Lucretia Magnusdotter (Gyllenhielm) (1562–1624) married to nobleman Christoffer von Warnstedt

With Anna von Haubitz

1. Helena Gyllenhielm (1572-1630) married to nobleman Wollmar Yxkull

Mother unknown:

1. Virginia

• "Magnus Gustavsson Vasa". Historiesajten.
• "Vadstena kloster och stad". Bengans historiasidor.

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